CPS2 multi crackling audio

[l_oliveira]

Looks like you did that for at least two other chips as well? Any reason other than initial troubleshooting?

It was also part of some research I did to get rid of the audio related pins under the board. The two chips between the rows of data pins for the audio ROMs are for audio and since the crackling is a audio issue, I focused on them. But turns out they were the receiving side of the problem, not the originating side... lol

 

[kuze]

Looks like you did that for at least two other chips as well? Any reason other than initial troubleshooting?

It was also part of some research I did to get rid of the audio related pins under the board. The two chips between the rows of data pins for the audio ROMs are for audio and since the crackling is a audio issue, I focused on them. But turns out they were the receiving side of the problem, not the originating side... lol

Makes sense, nice clean work with those tiny wires!

 

[fluxcore]

Fix seems to work fine! Yay!

 

[chrisapple]

Me too

 

[Darksoft]

Enameled wire is where it is

...

https://en.wikipedia.org/wiki/Magnet_wire

you're skilled, man!

 

[Darksoft]

The second method consists on lifting the leg 1 of U40 and connect this leg to any of the 3.3V points on the PCB like i.e leg 24 of U40. Additionally you need to add 8 Caps of 470 pF or similar to be soldered to the points shown below.

Guru used ceramic caps which are much easier to solder.

oops. there's a small typo there. voltage going to pin 1 comes from pin 24 of u40 sure, but its 3.3v
I used ceramic caps because that's all I had, plus they were ripped off some junk PCBs which is why they look old.

fixed!

 

[raidenmaniac1]

so what's the schedule for getting a fix if we are in the US? I don't feel confident doing the soldering an such . do we just get in contact with Mitsu or do we wait for some notification on this board ?

Thank you very much

 

[Mitsurugi-w]

so what's the schedule for getting a fix if we are in the US? I don't feel confident doing the soldering an such . do we just get in contact with Mitsu or do we wait for some notification on this board ?

Thank you very much

Wait until I post here. I have boxes everywhere in my house and I don't want to add a bunch of boxes waiting for parts. I don't want to look any more like a hoarder than I do now.

 

[atrainn]

I'm posting an alternative solution that maybe suitable for more people. I repeat this again. Make sure you know what you're doing as any damage that you make will void any warranty. Do it at your own risk

The second method consists on lifting the leg 1 of U40 and connect this leg to any of the 3.3V points on the PCB like i.e leg 24 of U40. Additionally you need to add 8 Caps of 470 pF or similar to be soldered to the points shown below.

Guru used ceramic caps which are much easier to solder. See attached. Notice that the picture only shows 4 capactiors, the other 4 go on the lower left pins of the connector closer to U40 (same pins as the cable solution with cables of Guru), that means pins C1, C2, C3 and C4.

Looks simple enough. I just ordered the caps. Thanks!

 

[pyJamma]

hi all.
Anyone local in Sydney Australia who is capable to do this?
If I have no luck I will organise to ship to Mr T Guru, but would prefer local first if possible.
Cheers!!

 

[Mr T Guru]

Pain in the ass to strip such small pieces, that was really the hardest part.

stripping kynar takes literally 1 second.
hold the wire flat on a piece of scrap wood.
put your soldering iron at the end of the wire about 2mm from the end then press down, wait 1 second and wipe away towards the end in one movement. repeat if necessary.
the wire is stripped instantly.
just don't do it on your kitchen bench or other valuable table otherwise your Mrs is going to kick you in the nuts.

 

[spilmer]

im still in the unsent batch, what will be the final solution for these boards ?

 

[Darksoft]

Everyone who didn't got his cartridge shipped yet will a tiny PCB already soldered in their kit that will be equivalent to those wires that you saw, so...you won't have to do anything it will be already fixed.

Cheers.

 

[aje_fr]

Just a little thought...
This TI chip are really shit ! (I got trouble with them too)
Did someone tried the NXP version (74LVC4245APW) ?

 

[l_oliveira]

Just a little thought...
This TI chip are really shit ! (I got trouble with them too)
Did someone tried the NXP version (74LVC4245APW) ?

It's not "shit". It's a special customization of 74xx245 chip which does voltage conversion.

 

[aje_fr]

Just a little thought...
This TI chip are really shit ! (I got trouble with them too)
Did someone tried the NXP version (74LVC4245APW) ?

It's not "shit". It's a special customization of 74xx245 chip which does voltage conversion.

I know that this chip are level translators
There is two manufacturer for this chip, TI and NXP.
Darksoft is using TI version while I'm proposing to give a try to the NXP one which give me many less troubles.

 

[l_oliveira]

You're the CPS1 multi game board guy, right? Welcome to the board!

 

[Mr T Guru]

I know that this chip are level translators There is two manufacturer for this chip, TI and NXP.
Darksoft is using TI version while I'm proposing to give a try to the NXP one which give me many less troubles.

I tried another type. 74LCX245. it doesn't fix it 100%. nearly but not fully.
problem is some timing related thing I think.
it's really difficult to diagnose.

 

[gojira54]

Nice one for the fix, had to give it a go

 

[Darksoft]

Nice one for the fix, had to give it a go

nice skills there!